There are a variety of protective masks or, colloquially, “gas masks,” to prevent users from inhaling toxic substances of all sorts. Such masks include negative pressure chemical, biological, radiological, and nuclear protective masks, known as CBRN protective masks in military parlance. The M45 joint service protective mask, part of the M40 series of masks, is among those in use by various branches of the United States Armed Services.
It is, of course, desirable to assure that the M45 masks and other protective masks in use by the military function and fit properly in order to protect the users from exposure to various toxins. In particular, the function of the outlet valve of the protective mask is often critical. Upon inhalation, the outlet valve must close to a sufficient degree to channel inhalation through the mask's canister without drawing in toxins from outside the mask. Conversely, upon exhalation, the outlet valve must open sufficiently to expel the breath, again without unacceptable leakage.
The outlet valve and other features of protective masks may be tested at the manufacturing facility. Factory tests of the outlet valves of protective masks often suffer from certain drawbacks and disadvantages. For example, operation of the outlet valve is generally tested by applying positive or negative pressure to the valve from inside of the mask. Such test results are often not acceptable to the armed services or other users. Such “inside” tests differ from testing the function of the valve from outside of the mask, and therefore such outside testing is generally preferred as an indication of serviceability and reliability.
The joint service mask leakage tester (JSMLT, in military parlance) is a portable testing device that has been developed for testing certain protective masks. However, the results obtained from the JSMLT are generally only as good as the connection between the JSMLT and the protective mask to be tested. In other words, unless the mask to be tested is properly secured or connected to the JSMLT, the test results related to function, serviceability, leakage, and proper fit of the mask may be inaccurate, producing either false positives or false negatives. In addition to the JSMLT, other portable testers are available for use and also require a secure connection between the mask being tested and the test device. Some of these devices include the TDA-99M Protective Mask Leakage Tester, which is the commercial equivalent of the JSMLT, and the TDA-99B which are both available commercially from Air Techniques International (ATI), of Owings Mills, Md.
The current connections between the JSMLT and masks to be tested suffer from various drawbacks and disadvantages, especially with regard to masks having outlet valves of irregular geometry, such as the M45. Current connections to the JSMLT sometimes may not create a sufficient seal with the outlet valve for accurate testing purposes. Establishing a suitable connection may be a cumbersome process at times, the ability to achieve the suitable connection may be inconsistent at other times, and the resulting connection may be unreliable at still other times.
There is thus a need to address the various drawbacks and disadvantages of the current apparatus for testing protective masks.